Abstract: A ferroelectric thin film is subjected to heat treatment in an active oxygen atmosphere containing an oxidizing gas such as ozone, N.sub.2 O, or NO.sub.2, thereby preventing occurrence of oxygen defects (oxygen vacancies) in the thin film, and avoiding a deterioration in dielectric characteristics, ferroelectric characteristics, and electric characteristics required for the ferroelectric thin film, such as a reduction in permittivity, an increase in leakage current, a reduction in remanent polarization, and an increase in coercive electric field. Thus, the ferroelectric thin film having stable characteristics can be formed. Further, a nonvolatile memory cell using this ferroelectric thin film as a capacitor is formed.

Abstract: Described are a stable semiconductor memory device which is not susceptible to the influence of a heat treatment temperature of a semiconductor substrate of reaction pressure in the CVD method and is free from the reduction in remanence caused by data writing in repetition; and a fabrication process of such a device which comprises forming, by the CVD method, a ferroelectric film containing as a component element bismuth, suing a bismuth alkoxide compound as a raw material, and using the ferroelectric film as a film for the formation of storage capacitance for a semiconductor memory device.

Abstract: A chopper folding machine including a chopper blade and a conveyor belt driven synchronously by a drive system for a folding apparatus put in juxtaposition with a printing machine, and a timing adjusting device provided in a drive system for at least one of the chopper blade and the conveyor belt for adjusting the timing of chopper folding. Thus, the timing of the conveyance of a signature, to be folded, by the conveyor belt and that of vertical movement of the chopper blade are adjusted.